Butler County Sheriff Richard Jones puts his message and face on a billboard in Middletown. Tough talk on immigration over the past year in Butler County has alarmed some of the area’s immigrants, many of whom work in construction in this booming area midway between Cincinnati and Dayton.

“People that had been in the United States for a while, who were planning to stay, now they feel scared,” Bravo said. He said he has sold at least 10 tickets in recent weeks to people who are moving to Michigan or other parts of Ohio, or who have decided to go back to Mexico.

Tough talk on immigration over the past year in Butler County has alarmed some of the area’s immigrants, many of whom work in construction in this booming area midway between Cincinnati and Dayton.

The community has been roiled by debate over the county’s resolve to crack down on employers of illegal immigrants, calls for a new law allowing local authorities to expel illegal immigrants, a state legislator’s bill to make English Ohio’s official language, and protests from civil rights activists after county authorities detained 18 undocumented immigrants.

Around the county, billboards show Sheriff Richard Jones — arms folded across his burly chest, a revolver at his side — warning, “Hire an Illegal-Break the Law,” with “Illegal Aliens Here” in a circle with a slash through it.

“The public is so frustrated with illegal immigration,” said Jones, who contends the hiring of illegal immigrants violates Ohio tax law. He has yet to arrest any employers. But county officials have talked about the possibility of denying building permits to contractors who hire illegal immigrants.

In Hamilton, the county seat, Luis Garcia, said he has seen several friends move to Kentucky because of the controversy. “I like it here, there’s a lot of work. But a lot of people are leaving,” said Garcia, 27, who said he works legally installing drywall.

Bravo, who is a legal immigrant, said Mexicans who are here illegally talk of life in “the Golden Cage” — going out only to work, then hiding in their homes.

Kevin Johnson, a professor and expert on civil rights and immigration law at University of California-Davis, sees frustration growing as the immigrant population spreads into the interior of the country, saddling local communities with added costs and straining services while there is legislative gridlock in Washington.

Hispanics are the fastest-growing immigrant group in this heavily Republican county, the home of House Majority Leader John Boehner, AK Steel and Miami University. The county of about 350,000 residents has more than 7,000 Hispanics, up from about 4,800 in 2000. The Hispanic population jumped fivefold in the 1990s in Hamilton, a city of about 62,000.

Hamilton elected one of Ohio’s first Hispanic mayors less than a decade ago. Adolf Olivas, whose parents were born in Cuba, was defeated for re-election in 2001 but said Butler County had for decades hosted “a nice, tight, Spanish-speaking community.”

The issue boiled over after the rape of a 9-year-old white girl in June 2005 in Hamilton. That sparked days of unrest, including the appearance of robed Ku Klux Klansmen and the torching of the house where the suspect, a Mexican immigrant who quickly disappeared, was staying.

“Because of one bad person, it hurts all of us,” said Antonio Ruiz, who helps build houses in Hamilton. The 36-year-old illegal Mexican immigrant said he now feels like a target: “When we go to the store, when we go to the gas station, we don’t know if we’re coming back.”

The American Civil Liberties Union decried as vigilantism the detention in May of 18 undocumented immigrants working at a construction site.